AUTHOR AND EDITOR INFORMATION

Section 1 of 12  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Further Reading
• Multimedia
• References

INTRODUCTION

Section 2 of 12  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Further Reading
• Multimedia
• References

Background

The symptoms of chronic bacterial prostatitis (CBP), which is category II in the 1995 NIH prostatitis classification system, are caused by bacterial infection. The nonbacterial form of chronic prostatitis is addressed in the eMedicine article Prostatitis, Nonbacterial. CBP causes an associated symptom complex and is characterized by recurrent urinary tract infections with a single organism that persists in the prostatic fluid.

The prostatitis symptom complex is very common. Approximately half of all men eventually develop symptoms consistent with prostatitis. This symptom complex accounts for approximately 25% of urologic evaluations in men, which is approximately 8% of all urology visits. In fact, the patient appointments for prostatitis outnumber those for cancer or benign prostatic hyperplasia (BPH).

Although the prostatitis symptom complex is not always caused by a bacterial infection, traditional teaching states that bacteria are the cause and require an antibiotic for treatment. This may explain why 50% of the patients with symptoms consistent with CBP are treated with antibiotics, yet only 5-10% of the men actually have a true bacteriologic condition that improves with treatment. Nonetheless, symptom improvement may also be due to a placebo effect or to an anti-inflammatory effect conferred by the antibiotic itself. 

A confounding factor is that fastidious organisms (eg, Chlamydia trachomatis, Ureaplasma urealyticum, Mycoplasma hominis) can cause prostatitis but do not grow in standard culture conditions; therefore, the condition may be interpreted as nonbacterial prostatitis. Continuing research, using sophisticated research methods, further elucidates that bacterial infection is the cause for more cases of prostatitis. Results from recent studies show that bacterial ribosomal ribonucleic acid (rRNA), by a reverse transcriptase–polymerase chain reaction (RT-PCR), assists in predicting a successful response to antibiotic treatment in patients with chronic prostatitis.

Pathophysiology

The prostate, because of its anatomic configuration, is the reservoir for the recurrent infections.

The normal prostate weighs approximately 18 g and measures 3 cm by 4 cm by 2 cm in length, width, and depth, respectively. It is located in the pelvis, underneath the symphysis pubis at the base of the bladder and on top of the rectum. The prostate is divided into 3 distinct zones, termed the central, transitional, and peripheral zones. These 3 zones fuse into a single glandular structure that completely surrounds the urethra. It is enclosed by a capsule composed of collagen, elastin, and smooth muscle.

The prostate is 70% glandular and 30% fibromuscular stroma. The glandular elements of the prostate are relatively simple tubuloalveolar glands and are lined with simple cuboidal or columnar epithelium. There are approximately 20 of these glands, and they branch out into the fibromuscular stroma. The prostate is innervated by sympathetic nerves from T-10 to L-1.

The peripheral zone of the prostate is composed of a system of ducts with a poor drainage system, which prevents the dependent drainage of secretions. As the prostate enlarges with age, causing obstructive symptoms, the urine refluxes into the prostatic ducts.

Urine reflux also may occur in urethral stricture disease. Refluxing urine, even when sterile, may cause chemical irritation and initiate tubule fibrosis and prostatic stone formation, which then lead to intraductal obstruction and stagnation of intraductal secretions. If trapped in these ducts, the infected material can serve as a nidus for relapsing infections, causing the symptoms of prostatitis. Infection of the prostate occurs via ascending urethral infection or reflux of infected urine into the prostatic ducts.

Infection often persists because antibiotics do not easily penetrate the prostate and no active transport mechanism exists whereby antibiotics can enter the prostatic ducts. Therefore, antibiotics depend on passive diffusion to enter the epithelial-lined prostatic glandular acini. The epithelial cells do not allow the free passage of antibiotics unless they meet certain criteria, ie, un-ionized, lipid-soluble, and not firmly protein-bound.

Another inhibiting factor is that prostatic fluid is acidic (pH of 6.4) compared with plasma (pH of 7.4), thus creating a pH gradient that further inhibits diffusion of acidic antibiotics into the prostatic fluid. Basic antibiotics are able to dissociate and concentrate in the prostatic fluid because of ion trapping within the prostatic fluid due to the pH gradient. Therefore, the best antibiotics for use in prostatitis have high dissociation constants (ie, measure of acid strength), are basic instead of acidic, and are not tightly protein-bound. This combination can allow up to a 6-fold higher concentration of antibiotic in the prostatic fluid compared to plasma.

Natural host defenses that prevent prostatitis include the flushing of the prostatic urethra by emptying the bladder, ejaculation, and the presence of a zinc-rich antibacterial polypeptide that has antibacterial effects against gram-positive and gram-negative bacteria. The prostate has the highest level of zinc concentration of any organ. Healthy men have very high zinc levels, whereas men with CBP have low prostatic zinc levels and normal serum zinc levels. Interestingly, oral zinc supplementation does not increase the prostatic zinc levels in men with CBP.

Spermine and spermidine are also natural host defenses in prostatic fluid. These impart the characteristic odor on ejaculate, and their antibacterial activity is directed mainly at gram-positive bacteria.

Frequency

United States

At some point in their lives, 35-55% of men have prostatitis symptoms. This accounts for approximately 25% of the men evaluated for a urologic problem, which is approximately 8% of all urology visits.

Mortality/Morbidity

• Prostatitis impairs the patient's quality of life to the same degree as coronary artery disease or Crohn disease.
• Recent studies show that prostatitis has the same effect on a patient's mental health as does diabetes mellitus and congestive heart failure.¹

Age

• Symptoms of prostatitis are very common in men aged 36-50 years.
• Prostatitis is the most common urologic problem in men younger than 50 years and the third most common in older men.
• Recent studies using the US National Institutes of Health-Chronic Prostatitis Symptom Index (NIH-CPSI) found that the prevalence of prostatitis symptoms was 10% in a population of men aged 20-74 years. See Image 1.

CLINICAL

Section 3 of 12  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Further Reading
• Multimedia
• References

History

Patients with chronic bacterial prostatitis (CBP) often present with myriad subjective complaints. Only a few of these complaints offer diagnostic clues for CBP because the complaints are often not of an unusual nature and are not specific for CBP. If culture results are positive, an expressed prostatic secretion (EPS) that contains bacteria or more than 10 WBCs per high-power field (WBCs/hpf) confirms the diagnosis.

• Genitourinary pain occurs in the perineal area, penile tip, testicles, rectum, lower abdomen, and back.
• Patients can also have irritative or obstructive urologic symptoms such as frequency, urgency, dysuria, decreased force of the urinary stream, nocturia, and postvoid dribbling.
• Other symptoms include a clear-to-milky urethral discharge, ejaculatory pain, hematospermia, and sexual dysfunction.

Physical

Physical examination findings are often nonspecific.

• The classic presentation in a symptomatic patient is an enlarged, soft, or, boggy gland that is moderately-to-severely tender upon palpation.
• In some cases, an examiner is able to palpate prostatic stones. Because stones may be a nidus for recurrent infections, they may offer a significant clue to the cause of the recurrences.

Causes

Causative organisms include following:

• Escherichia coli
• Klebsiella pneumoniae
• Pseudomonas aeruginosa
• Proteus species
• Staphylococcus species
• Enterococcus species
• Trichomonas species
• Candida species
• C trachomatis
• U urealyticum
• M hominis

DIFFERENTIALS

Section 4 of 12  

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• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Further Reading
• Multimedia
• References

Other Problems to be Considered

Acute prostatitis
Prostatic stones
Anatomic obstruction due to prostatic hyperplasia, urinary stricture disease, or bladder neck dysfunction

WORKUP

Section 5 of 12  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Further Reading
• Multimedia
• References

Lab Studies

• Microscopic examination  
• • Commonly, chronic prostatitis (category II in the 1995 NIH prostatitis classification system) is diagnosed after microscopic examination of the EPS and a positive culture finding after a prostatic massage. If a patient presents with symptoms of an acute urinary tract infection and/or the patient is febrile, an EPS should not be obtained because the patient likely has acute prostatitis. In this situation, a vigorous prostatic massage may result in urinary sepsis.
  • The generally accepted level of WBCs in an EPS for a diagnosis of chronic prostatitis (category II) is more than 10 WBCs/hpf (40X objective) or an observation of clumping WBCs with the presence of oval fat bodies and a positive EPS culture finding. Category III prostatitis is divided into IIIa and IIIb based on whether greater or fewer than 10 WBCs are seen on microscopic examination of the EPS, respectively. However, the management approaches for these two categories do not differ.
  • Finding WBCs in an EPS is not diagnostic of chronic bacterial prostatitis (CBP) because this finding is commonly associated with nonbacterial prostatitis, urethritis, prostatic stones, or recent ejaculation. 
• Positive urine culture findings after a prostatic massage  
• • Performing this procedure helps confirm the diagnosis of CBP.
  • The classic 4-glass Meares-Stamey test for localization of the infection to the prostate is cumbersome and impractical. A more sensitive and practical test that is simpler to perform is preprostatic and postprostatic massage urine culture.²
  • The ejaculate can also be cultured. This may indicate a prostatic infectious source.
  • Carefully observe the culture for a colony count that is 10 times higher in the postprostatic massage culture compared to the preprostatic massage culture, which confirms CBP. This is the widely accepted standard.
  • Perform the prostatic massage during the rectal examination by kneading the prostate from front to back and from lateral to medial until a milky fluid is obtained from the urethra. This may require as long as a minute of fairly vigorous massage; therefore, inform the patient of the intended plan and goal. Sometimes, milking the urethra hastens the appearance of the fluid. Then, touch the fluid to a microscopic slide for examination.
  • The pH of prostatic fluid rises when infection is present, from 6.5 to higher than 8.0.
  • Prostate-specific antigen (PSA) levels are often elevated. Do not construe this finding as an elevation associated with prostate cancer unless the level remains elevated after repeat testing. Repeat testing should be performed 6 weeks after resolution of the prostatitis.

Imaging Studies

• Transrectal ultrasonography 
• • This study is not helpful unless an abscess is present. Abscesses are extremely rare, but if present, patients may also have a high fever and appear quite ill. CT scanning may also be helpful in this situation if transrectal ultrasonography is not available. MRI may also be used but is usually not as readily available in most acute situations.
  • Transrectal ultrasonography findings may also help identify prostatic stones. In certain patients with frequent recurrences, prostatic stones may be a contributing factor in CBP.

Procedures

• Prostate biopsy  
• • This is the most definitive but least practical modality used to diagnose bacterial prostatitis. It is also potentially dangerous for the patient.
  • Viewing the specimen under microscopy can help identify a focal infiltration of inflammatory cells into the prostatic stroma. The specimen also serves as a source from which to culture organisms. However, in the face of an active infection such as acute prostatitis, performing a biopsy could precipitate sepsis. Therefore, prostate biopsy is not recommended as a diagnostic modality.
  • On the other hand, category IV prostatitis is diagnosed using prostate biopsy. Category IV prostatitis is asymptomatic but may be responsible for elevations in PSA levels, resulting in the need for a diagnostic biopsy to help exclude prostate cancer.
• If the patient has frequent recurrences of chronic prostatitis, other tests may help exclude an anatomic obstruction due to prostatic hyperplasia, urinary stricture disease, or bladder neck dysfunction. If this is the case, appropriate treatment (eg, transurethral incision of a urethral stricture, transurethral resection of the prostate or bladder neck) may be indicated.
• Retrograde urethrography, uroflowmetry, and postvoid residual testing are described as follows:  
• • Retrograde urethrography is performed to help confirm the presence of a urethral stricture. It is performed by injecting contrast into the urethral meatus and obtaining pelvic radiography. If a stricture is present, narrowing of urethral caliber is observed.
  • Uroflowmetry is a simple urodynamic test to help evaluate the rate of urine flow over time. It is used in patients with prostatitis to help evaluate for obstruction secondary to a urethral stricture or prostatic enlargement. Results are obtained in graphical form. Normal study results show a rapid rise to a peak and then a gradual drop-off back to baseline. A urethral stricture is indicated by a rapid rise to a low point, a plateau for the remainder of the study, and then a drop-off at the termination of the study. In prostatic enlargement, a wide variety of patterns is present, but the peak flow is usually less than 15 mL/s, and a stop-start pattern may also be present. To help delineate abnormalities and to differentiate a stricture from prostatic enlargement, cystoscopy should be performed.
  • Postvoid residual testing measures the volume of urine left in the bladder immediately after voiding. This volume can be measured by catheterizing the bladder or by using a bladder scanner. Although the results are nonspecific, they can give clues to the presence of lower tract dysfunction, which may require surgical intervention to relieve prostatic obstruction or urethral stricture.

Histologic Findings

Chronic inflammation is common after biopsy specimens have been obtained to help evaluate for prostate cancer. Findings usually include large focal lymphocytic infiltrates amid the normal prostatic stroma; however, biopsy rarely, if ever, is used to diagnose prostatitis. If an asymptomatic patient is found to have inflammation in the prostatic tissue, this is categorized as category IV prostatitis, ie, asymptomatic inflammatory prostatitis.

TREATMENT

Section 6 of 12  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Further Reading
• Multimedia
• References

Medical Care

If the postprostatic massage urine culture results are positive, then successful treatment is likely. However, because of the difficulty in obtaining sufficient material for culture, a trial of antibiotics is worthwhile if clinical evidence strongly suggests chronic prostatitis.

Recent studies using extensive research methods (eg, RT-PCR) show evidence of bacterial infection despite negative findings after urine culture. Negative culture results occur for various reasons, including insufficient sample volume, initiation of antibiotics prior to obtaining an EPS, and the presence of fastidious organisms. These patients often have symptom improvement after antibiotic treatment.

A query of high-risk behaviors, multiple partners, unprotected anal intercourse, and the possibility of sexually transmitted diseases may help. If doubt remains, conduct a 2-week trial of an appropriate antimicrobial therapy to try to alleviate the symptoms. If the symptoms improve, prescribe a complete course of antibiotics. Because this is a not an acute infection, as in most cases, help alleviate the symptoms using symptomatic treatment with analgesics and alpha-blockers until confirmatory culture results are available. Sitz baths also may provide symptomatic improvement.

• Antimicrobial therapy  
• • The choice of antimicrobial is critical because the prostate has an epithelial lining and a pH gradient that inhibits antimicrobials from entering the prostatic acini. Ideal antibiotics have a higher dissociation constant to allow diffusion of their un-ionized components into the prostate. In addition, if the antibiotic is basic, it can readily concentrate much higher in prostatic fluid than in the plasma because of the pH gradient.
  • Prostatic stones (if present) may be a nidus for recurrent infection, and they are difficult to treat with antibiotic therapy; therefore, surgical therapy in the form of a transurethral resection of the prostate (TURP) may be indicated.
  • The best antibiotic choices include trimethoprim-sulfamethoxazole (TMP-SMZ) at 80-400 mg given twice a day and fluoroquinolone antibiotics (eg, ciprofloxacin at 500 mg or ofloxacin at 400 mg) twice a day or gatifloxacin/moxifloxacin at 400 mg daily. TMP-SMZ yields a 33-50% cure rate with a 4- to 6-week course of treatment. Fluoroquinolones yield a similar cure rate with a 4-week course.
  • TMP-SMZ is significantly less expensive; however, consider a fluoroquinolone (eg, ofloxacin [Floxin]) if the patient is younger than 35 years and sexually active with multiple partners because it also has activity against chlamydial and gonorrheal organisms.
  • For patients in whom oral antibiotic therapy fails, use other antibiotics to treat chronic bacterial prostatitis (CBP). These may include carbenicillin or doxycycline or injections of gentamicin, either parenterally or directly into the prostate.
  • Patients with persistent infections, especially those who have symptom improvement while on antibiotics but quickly have a recurrence after finishing a course of antibiotics, may benefit from suppressive therapy with low daily doses of antibiotics. Good choices are tetracycline, nitrofurantoin, nalidixic acid, cephalexin, or trimethoprim. Bacteria in CBP are usually sensitive strains, even after a number of antibiotic treatment regimens have been tried.
• Other medical treatments  
• • The addition of nonsteroidal anti-inflammatory drugs and alpha-blockers (eg, terazosin at 1-10 mg, doxazosin at 1-8 mg) help with symptom relief. The alpha-blockers can help decrease recurrences by diminishing urinary obstruction due to prostate enlargement or congestion secondary to inflammation. Saw palmetto, an herbal supplement well known as a treatment for prostatic enlargement, has also been used.³ Saw palmetto is hypothesized to act similar to 5-alpha-reductase inhibitors. Finasteride, a 5-alpha-reductase inhibitor, has been shown to be effective in relieving symptoms. Quercetin, a polyphenolic flavonoid with antioxidant properties found in green tea, onions, and oranges, has also has been shown to significantly decrease symptoms.
  • In addition, instruct the patient to ejaculate a minimum of every 3 days while on antibiotic therapy to help with drainage of the prostatic ducts.
  • Sitz baths also may provide some symptom improvement.

Surgical Care

Surgery is usually not indicated for chronic prostatitis. However, in select situations when a patient has recurrent episodes of chronic prostatitis and improves with antibiotics, TURP or transurethral vaporization of the prostate (TUVP) may remove a nidus of infection. This nidus may be in the form of prostatic stones. These stones are usually visible on transrectal sonograms.

• TURP/TUVP is performed in a standard fashion after preoperative antibiotics have been administered.  
• • Routine preoperative evaluation should be performed when planning for TURP/TUVP.
  • A routine TURP/TUVP should be performed.
  • Routine postoperative care for TURP/TUVP should be used in these patients.

Activity

Frequent ejaculation (every 3 days), either through intercourse or masturbation, may help alleviate symptoms.

Daily sitz baths and perianal massage may also help with the discomfort associated with chronic prostatitis.

MEDICATION

Section 7 of 12  

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• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Further Reading
• Multimedia
• References

The goals of pharmacotherapy are to eradicate the infection, to reduce morbidity, and to prevent complications.

Drug Category: Antibiotics

Therapy must cover all likely pathogens in the context of this clinical setting.

Drug Name	Moxifloxacin (Avelox)
Description	Inhibits the A subunits of DNA gyrase, resulting in inhibition of bacterial DNA replication and transcription.
Adult Dose	400 mg PO qd
Pediatric Dose	<18 years: Not recommended >18 years: Administer as in adults
Contraindications	Documented hypersensitivity; known Q-T prolongation, concurrent administration of drugs that cause Q-T prolongation
Interactions	Antacids, electrolyte supplements reduce absorption; loop diuretics, probenecid, cimetidine increase serum levels; NSAIDs enhance CNS stimulating effect May increase toxicity of theophylline, caffeine, cyclosporine, and digoxin (monitor digoxin levels); may increase effects of anticoagulants (monitor PT); ferrous sulfate decreases bioavailability (administer moxifloxacin 4 h prior or 8 h following ferrous sulfate); coadministration with drugs that prolong QTc interval (quinidine, procainamide, amiodarone, sotalol, erythromycin, tricyclic antidepressants) increase risk of life-threatening arrhythmia
Pregnancy	C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions	In prolonged therapy, perform periodic evaluations of organ system functions (eg, renal, hepatic, hematopoietic); superinfections may occur with prolonged or repeated antibiotic therapy; fluoroquinolones have induced seizures in CNS disorders and caused tendinitis or tendon rupture

Drug Name	Sulfamethoxazole and trimethoprim (Bactrim, Bactrim DS, Septra, Septra DS)
Description	Inhibits bacterial growth by inhibiting synthesis of dihydrofolic acid.
Adult Dose	80 mg TMP/400 mg SMZ PO bid for 4-6 wk
Pediatric Dose	Not established
Contraindications	Documented hypersensitivity; megaloblastic anemia due to folate deficiency
Interactions	May increase PT when used with warfarin (perform coagulation tests and adjust dose accordingly); coadministration with dapsone may increase blood levels of both drugs; coadministration of diuretics increases incidence of thrombocytopenia purpura in elderly persons; phenytoin levels may increase with coadministration; may potentiate effects of methotrexate in bone marrow depression; hypoglycemic response to sulfonylureas may increase with coadministration; may increase levels of zidovudine
Pregnancy	C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions	Discontinue at first appearance of skin rash or sign of adverse reaction; obtain CBC counts frequently; discontinue therapy if significant hematologic changes occur; goiter, diuresis, and hypoglycemia may occur with sulfonamides; prolonged IV infusions or high doses may cause bone marrow depression (if signs occur, administer 5-15 mg/d leucovorin); caution in folate deficiency (eg, persons with chronic alcoholism, elderly persons, those receiving anticonvulsant therapy, or those with malabsorption syndrome); hemolysis may occur in G-6-PD deficiency; patients with AIDS may not tolerate or respond to TMP-SMZ; caution in renal or hepatic impairment (perform urinalyses and renal function tests during therapy); administer fluids to prevent crystalluria and stone formation

Drug Name	Ciprofloxacin (Cipro)
Description	Fluoroquinolone with activity against pseudomonas, streptococci, MRSA, Streptococcus epidermidis, and most gram-negative organisms but no activity against anaerobes. Inhibits bacterial DNA synthesis and, consequently, growth.
Adult Dose	500 mg PO bid for 4 wk
Pediatric Dose	Not established
Contraindications	Documented hypersensitivity
Interactions	Antacids, iron salts, and zinc salts may reduce serum levels; administer antacids 2-4 h before or after taking fluoroquinolones; cimetidine may interfere with metabolism of fluoroquinolones; reduces therapeutic effects of phenytoin; probenecid may increase serum concentrations; may increase toxicity of theophylline, caffeine, cyclosporine, and digoxin (monitor digoxin levels); may increase effects of anticoagulants (monitor PT)
Pregnancy	C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions	In prolonged therapy, perform periodic evaluations of organ system functions (eg, renal, hepatic, hematopoietic); adjust dose in renal function impairment; superinfections may occur with prolonged or repeated antibiotic therapy

Drug Name	Ofloxacin (Floxin)
Description	Penetrates prostate well and is effective against Neisseria gonorrhea and C trachomatis. Derivative of pyridine carboxylic acid with broad-spectrum bactericidal effects.
Adult Dose	400 mg PO bid for 4 wk
Pediatric Dose	Not established
Contraindications	Documented hypersensitivity
Interactions	Antacids, iron salts, and zinc salts may reduce serum levels; administer antacids 2-4 h before or after taking fluoroquinolones; cimetidine may interfere with metabolism of fluoroquinolones; ciprofloxacin reduces therapeutic effects of phenytoin; probenecid may increase ciprofloxacin serum concentrations; may increase toxicity of theophylline, caffeine, cyclosporine, and digoxin (monitor digoxin levels); may increase effects of anticoagulants (monitor PT)
Pregnancy	C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions	In prolonged therapy, perform periodic evaluations of organ system functions (eg, renal, hepatic, hematopoietic); adjust dose in renal function impairment; superinfections may occur with prolonged or repeated antibiotic therapy

Drug Name	Carbenicillin (Geocillin)
Description	Inhibitor of cell wall mucopeptides and effective during stage of active growth. Indicated for prostatitis caused by E coli, Enterobacter species, Proteus mirabilis, and enterococci.
Adult Dose	2 tab PO q6h
Pediatric Dose	Not established
Contraindications	Documented hypersensitivity
Interactions	Effects are reduced with tetracycline coadministration; at high concentrations in an IV line, may physically inactivate aminoglycosides; levels are increased with probenecid; coadministration with aminoglycosides has synergistic effects
Pregnancy	B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
Precautions	Perform CBC count prior to therapy and weekly during therapy; monitor for liver function abnormalities by measuring AST and ALT during therapy; urinalysis, BUN, and creatinine determinations should be performed during therapy and dose adjusted if these values become elevated; in known or suggested renal impairment, adjust dose and monitor blood levels (these measures help prevent possible neurotoxic reactions)

Drug Name	Doxycycline (Doryx, Periostat, Vibra-Tabs)
Description	Inhibits protein synthesis and thus bacterial growth by binding to 30S and possibly 50S ribosomal subunits of susceptible bacteria.
Adult Dose	200-300 mg PO divided bid
Pediatric Dose	Not established
Contraindications	Documented hypersensitivity; severe hepatic dysfunction
Interactions	Bioavailability decreases with antacids containing aluminum, calcium, magnesium, iron, or bismuth subsalicylate; tetracyclines can increase hypoprothrombinemic effects of anticoagulants; tetracyclines can decrease effects of oral contraceptives, causing breakthrough bleeding and increased risk of pregnancy
Pregnancy	D - Fetal risk shown in humans; use only if benefits outweigh risk to fetus
Precautions	Photosensitivity may occur with prolonged exposure to sunlight or tanning equipment; reduce dose in renal impairment; consider drug serum level determinations in prolonged therapy; tetracycline use during tooth development (last half of pregnancy through age 8 y) can cause permanent discoloration of teeth; Fanconilike syndrome may occur with outdated tetracyclines

Drug Name	Gentamicin (Garamycin, Jenamicin)
Description	Aminoglycoside antibiotic for gram-negative coverage. Used in combination with both an agent against gram-positive organisms and one that covers anaerobes. Not the DOC. Consider if other less toxic drugs are contraindicated, when clinically indicated, and in mixed infections caused by susceptible staphylococci and gram-negative organisms.
Adult Dose	1.5 mg/kg/dose IV/IM
Pediatric Dose	Not established
Contraindications	Documented hypersensitivity; non–dialysis-dependent renal insufficiency
Interactions	Coadministration with other aminoglycosides, cephalosporins, penicillins, and amphotericin B may increase nephrotoxicity; because aminoglycosides enhance effects of neuromuscular blocking agents, prolonged respiratory depression may occur; coadministration with loop diuretics may increase auditory toxicity of aminoglycosides; possible irreversible hearing loss of varying degrees may occur (monitor regularly)
Pregnancy	D - Fetal risk shown in humans; use only if benefits outweigh risk to fetus
Precautions	Narrow therapeutic index (not intended for long-term therapy); caution in renal failure (not on dialysis), myasthenia gravis, hypocalcemia, and conditions that depress neuromuscular transmission; adjust dose in renal impairment

Drug Category: Alpha-adrenergic blocking agents

These agents relax the smooth muscle to the bladder neck, thus reducing bladder outlet obstruction.

Drug Name	Doxazosin (Cardura)
Description	Counteracts alpha1–induced adrenergic contractions of bladder neck, facilitating urinary flow in presence of prostate inflammation.
Adult Dose	1 mg PO qd; may increase to 2 mg qd thereafter and titrate to higher doses over several wk as necessary; not to exceed 8 mg/d
Pediatric Dose	Not established
Contraindications	Documented hypersensitivity
Interactions	Effects decrease with coadministration of NSAIDs; effects increase with coadministration of diuretics and antihypertensive medications
Pregnancy	C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions	Caution in renal impairment; may cause marked hypotension following first dose

Drug Category: Antiandrogens

These agents inhibit the conversion of testosterone into dihydrotestosterone.

FOLLOW-UP

Section 8 of 12  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Further Reading
• Multimedia
• References

Further Outpatient Care

• If the patient is treated long-term with antibiotics, ensure that relocalization studies of the prostate (ie, preprostatic and postprostatic massage urine cultures after treatment) are conducted to conclude that the bacteria are eliminated. If repeat cultures return positive results, prescribe a second course of antibiotics with a drug that has a different mechanism of action.

In/Out Patient Meds

• If repetitive courses fail and the patient has improved symptomatology while on antibiotics, consider long-term low-dose suppressive therapy. Examples of suppressive therapy are Bactrim (single strength qhs), trimethoprim (100 mg qhs), ciprofloxacin (250 mg qhs), and ofloxacin (200 mg qhs).

Complications

• Infection often persists because antibiotics do not penetrate the prostate easily and no active transport mechanism exists whereby antibiotics can enter the prostatic ducts. Another inhibiting factor is that prostatic fluid is acidic compared to plasma, thus creating a pH gradient further inhibiting diffusion of acidic antibiotics into the prostatic fluid. See Antimicrobial therapy for guidance on antibiotic selection.

Prognosis

• Treatment success rates with TMP-SMZ approach 30-40%, and success rates with fluoroquinolones are 60-90%.
• Treat relapses with a 3-month course of antibiotics. If this fails, consider a low suppressive dose of antibiotics (eg, Bactrim at single strength qhs, trimethoprim at 100 mg qhs, ciprofloxacin at 250 mg qhs, ofloxacin at 200 mg qhs).

Patient Education

• For excellent patient education resources, visit eMedicine's Prostate Health Center and Men's Health Center. Also, see eMedicine's patient education articles Understanding the Male Anatomy, Prostate Infections, and Urinary Tract Infections.

MISCELLANEOUS

Section 9 of 12  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Further Reading
• Multimedia
• References

Special Concerns

• Continued research of occult bacterial infections as the cause of prostatitis syndrome is ongoing and will lead to further effective treatments for prostatitis symptoms.
• Recent studies have shown a possible association between prostate cancer and prostatitis.^{4, 5} Anti-inflammatory agents that target cyclooxygenase are hypothesized to decrease this risk.

FURTHER READING

Section 10 of 12  

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• Introduction
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• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Further Reading
• Multimedia
• References

For additional information, see Medscape’s Prostatitis Resource Center.

MULTIMEDIA

Section 11 of 12  

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• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Further Reading
• Multimedia
• References

Media file 1:  Chronic Bacterial Prostatitis. US National Institutes of Health chronic prostatitis symptom index.
	View Full Size Image
Media type:  Graph

REFERENCES

Section 12 of 12

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Further Reading
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Article Last Updated: Mar 13, 2008